Battling brain-eating amoeba: Enigmas surrounding immunity to Naegleria fowleri

摘要

Free-living amoebas (FLA) are remarkable single-cell engines, foraging their way through a range of environments. However, occasionally these amoebas find themselves within a human host, and an unusual and deadly opportunistic infection unfolds. The FLA Naegleri fowleri is the causative agent for an invasive and lethal form of meningoencephalitis known as primary amoebic meningoencephalitis (PAM). According to the CDC, 147 patients have been diagnosed with PAM in the United States since 1962. Yet, because distinguishing PAM from other types of meningitis and encephalitis can be difficult, it’s likely that many cases of PAM are simply never identified, especially in areas of the world with under-resourced healthcare systems. Because N. fowleri is a thermophilic organism, rising global temperatures will prolong growth seasons and expand compatible habitats. In fact, although N. fowleri infection and PAM are not a nationally notifiable disease, there is evidence that the latitude of reported infections has broadened over the past 10 to 15 years [1]. When paired with potentially increased water recreation, a warming climate may facilitate a collision course of amoebic growth and human activity.